APPLICANT?S DESCRIPTION: The objective of this proposal is to develop a commercial HLA (human leucocyte antigen) typing system using a microsphere-based DNA probe array. Characterization of HLA gene at DNA level has become a crucial tool in identifying HLA compatible donor-recipient pairs for successful human organ/marrow transplantation. Here, we describe an advanced yet tangible method of HLA typing for the five major HLA loci, HLA-A, B, C, DRB, and DQB to accommodate the needs of clinical laboratories. The microsphere-based array platform has a unique combined advantage of DNA probe array, and flexibility, cost-effectiveness, and sample processing capability of flow cytometry. Multi-analyte DNA hybridization assay using a panel of HLA locus-specific probe is conducted and analyzed in a single reaction. In phase II period, we will continue and expand probe development for both low and high resolution typing of the five major HLA loci, develop sample amplification method, develop data analysis software, and rigorously validate the final system through beta-testing. Flexibility, cost-effectiveness, and automation potential of the proposed system is expected fulfill the existing needs of HLA typing at DNA level for laboratories involved in solid organ transplant as well as high throughput screening for the national bone marrow donor registry. PROPOSED COMMERCIAL APPLICATION: Not Available